Rebekah, I kind of struggled with these

Luanne Jorewicz

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Message From NASA Administrator Michael GriffinthWith this, an addendum to the 10 revision of NASA’s Implementation Plan for Space Shuttle Return to Flight and Beyond, our Shuttle program team presents the culmination of 29 months of intensive effort to make the Space Shuttle system, and NASA as a whole, stronger, and safer. Following our rigorous Flight Readiness Review, the launching of the Space Shuttle Discovery and its seven person crew on the STS-114 mission is now within sight. This flight will test and validate hardware and procedures developed since the tragic loss of Columbia and its valiant crew. The Discovery mission represents an important step in our nation’s unfolding journey of exploration that will take astronaut pioneers back to the Moon, to Mars, and beyond. Return to Flight has been a massive effort, focusing the energies of every technical discipline across all the NASA Centers and Space Shuttle contractors on a very specific objective. I am proud of this Agency for its hard work, diligence, and professionalism in working toward the goal of flying the Shuttle safer than ever before. I also appreciate the work of the Columbia Accident Investigation Board and the Stafford-Covey Return to Flight Task Group. The members of both bodies have provided valuable recommendations and analysis to our Shuttle program. We know from hard experience that human space exploration is not and will never be without risk. Nothing ...

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• Publié par: Nifor
• Nombre de lectures: 36
• Langue: English

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Message From NASA Administrator Michael Griffin

Return to Flight has been a massive effort, focusing the energies

of every technical discipline across all the NASA Centers and

Space Shuttle contractors on a very specific objective. I am

proud of this Agency for its hard work, diligence, and

professionalism in working toward the goal of flying the Shuttle

safer than ever before. I also appreciate the work of the

Columbia

Accident Investigation Board and the Stafford-Covey

Return to Flight Task Group. The members of both bodies

have provided valuable recommendations and analysis to our

Shuttle program.

With this, an addendum to the 10

th

revision of

NASA’s

Implementation Plan for Space Shuttle Return to Flight and Beyond

, our

Shuttle program team presents the culmination of 29 months of

intensive effort to make the Space Shuttle system, and NASA as

a whole, stronger, and safer.

Following our rigorous Flight Readiness Review, the launching

of the Space Shuttle

Discovery

and its seven person crew on the

STS-114 mission is now within sight. This flight will test and

validate hardware and procedures developed since the tragic loss

of

Columbia

and its valiant crew. The

Discovery

mission represents

an important step in our nation’s unfolding journey of

exploration that will take astronaut pioneers back to the Moon,

to Mars, and beyond.

We know from hard experience that human space exploration is

not and will never be without risk. Nothing great worth doing

ever is. But I am firmly convinced that this nation and this

agency can execute as safely as humanly possible the bold and

noble exploration agenda set forth by President George W.

Bush, beginning with the STS-114 mission.

Michael D. Griffin

NASA’s Implementation Plan for Space Shuttle Return to Flight and Beyond

July 7, 2005

Tenth Edition Addendum

July 7, 2005

Summary

At a plenary meeting held on June 8, 2005, the Stafford Covey Return to Flight Task

Group closed five Return to Flight (RTF) recommendations and the Space Shuttle

Program (SSP) raising the bar action SSP-3, Contingency Shuttle Crew Support

(CSCS). The Task Group held its final plenary meeting on June 27, 2005. At that

meeting, the Task Group discussed NASA’s efforts to address the remaining three

Columbia

Accident Investigation Board (CAIB) RTF actions: 3.2-1, External Tank

Thermal Protection System Modifications; 3.3-2, Orbiter Hardening and Thermal

Protection System Impact Tolerance; and 6.4-1, Thermal Protection System On-

Orbit Inspection and Repair. In each instance, the Task Group felt that NASA had

completed significant work but had not fully complied with all elements of the Task

Group’s interpretation of the CAIB’s intent. The Task Group said,

“

The remaining

three recommendations were so challenging that NASA could not completely

comply with the intent of the CAIB, but conducted extensive study, analyses,

hardware modifications, design certifications and made substantive progress.

However, the inability to fully comply with all of the CAIB recommendations should

not imply that the Space Shuttle is unsafe.”

CAIB Recommendation 3.2-1 called for NASA to initiate an aggressive program to

eliminate all debris shedding from the External Tank at its source. NASA did initiate

an aggressive program to eliminate debris. Early in this process we recognized that

eliminating all debris is impossible given the existing Space Shuttle configuration.

The Task Group chose to interpret this Recommendation in a more restrictive

fashion and held NASA to a standard of eliminating all sources of critical debris from

the External Tank. For several months NASA strove to identify the debris that

would be shed from the External Tank and the ability of the Space Shuttle to

withstand damage. This complicated, iterative process still showed that all critical

debris could not be eliminated. NASA’s debris transport and impact tolerance testing

and analysis also showed that it was not necessary in order to significantly reduce the

likelihood of damage. However, NASA’s program has resulted in a significant

reduction in both foam and ice debris that will be shed during launch and ascent.

NASA revamped the manual foam application and inspection process; redesigned

critical areas of the External Tank and Solid Rocket Boosters; and verified our new

processes to ensure that we would not release foam debris over the critical threshold.

We have also fully eliminated the proximate cause of the

Columbia

Accident by

redesigning the bipod foam area. NASA also took steps to reduce the possibility of

critical ice debris by installing a heater on the External Tank feed line bellows and

developing more restrictive criteria for our pre-launch ice inspections. Because of

these improvements, we do not expect to see any critical foam debris, and the risk of

critical ice debris has been reduced to an acceptable level.

The Task Group lauded NASA’s work to understand the impact and damage

tolerance of the Space Shuttle’s thermal protection system and to harden the thermal

protection system tiles against damage as called for in CAIB Recommendation 3.3-2.

However, the Task Group did not close Recommendation 3.3-2 because NASA

cancelled its long-term program to harden the existing Reinforced Carbon-Carbon

material. NASA cancelled the development program after the planned service life of

the Shuttle was shortened to 2010, consistent with the Vision for Space Exploration.

NASA’s Implementation Plan for Space Shuttle Return to Flight and Beyond

July 7, 2005

This decision was based on NASA’s assessment of the relative value of investing in along-term capability that might not be

available prior to the Shuttle’s retirement against the other critical investments needed to ensure the continued safe operations

of the Space Shuttle.

Finally, the Task Group acknowledged the significant accomplishments NASA made in implementing CAIB Recom-

mendation 6.4-1, Thermal Protection System Inspection and Repair, but felt that NASA had not met the intent of the CAIB

relative to thermal protection system repair. The Task Group felt that NASA’s efforts relative to inspection did meet the

CAIB’s intent. At return to flight, NASA will be fielding an unprecedented capability to detect and inspect the Orbiter’s

thermal protection system on-orbit. We will also have a limited capability to repair damage to the Orbiter; on our first two

flights, the new tools and techniques associated with this capability will be tested in the combined environments of space by

manifesting a number of the techniques on the STS-114 and STS-121 missions. The Space Shuttle’s thermal protection

system was not designed to be repaired on-orbit. As a result, developing repair techniques has been extremely challenging;

however, we have put forth our best efforts to develop these capabilities. We acknowledge that our repair capabilities will be

limited; we accept the risk associated with those limitations, and we continue work to develop these capabilities. When we

return to flight, a combination of Shuttle and International Space Station assets will allow us to detect damage at the critical

threshold and inspect any suspect areas with greater detail. NASA had pursued a repair capability at various points over the

life of the Shuttle Program. Until now, thermal protection system repair was a technical challenge that eluded us. On the first

two flights, STS-114 and STS-121, we will test an array of repair tools and techniques for both thermal protection system tile

and the reinforced carbon-carbon panels that make up the wing leading edge. We expect these repair techniques to allow us

to fix a range of tile damage, including lost tiles and cracks and holes in the wing leading edge up to 4 inches in diameter.

Because of the significant work done to improve the Space Shuttle system and reduce the risk that critical debris will be

liberated during ascent, we do not expect to see damage that requires repair; however, it is prudent to field the capabilities we

have at return to flight so that we can respond in the unlikely event that critical damage occurs.

Since the loss of the Space Shuttle

Columbia

and her crew, NASA has developed and implemented many safety improvements

to the Space Shuttle system to eliminate, reduce, or control the known risks. However, human space flight is inherently risky;

at RTF, there will be some residual risk which NASA must accept. To the greatest extent that it is practical and possible on

the ground, NASA has thoroughly reviewed and tested the new capabilities developed to detect, inspect, and repair damage to

the Orbiter. However, many of these capabilities can only be verified by actual flight operations in the environment of space.

The first two RTF Space Shuttle missions will be the test flights that validate our new designs and procedures.

At the Flight Readiness Review for STS-114, NASA formally reviewed the actions taken to prepare the Space Shuttle for

return to flight and accepted the level of risk remaining in the Space Shuttle system. NASA is now ready to return the Space

Shuttle safely to flight. The Space Shuttle

Discovery

and her crew, commanded by Col. Eileen Collins, is planned for launch

July 13, 2005.

Implementation Plan

Updates

Update the following in the June 3, 2005, 10

th

Edition of NASA’s Implementation Plan for Space Shuttle Return to

Flight and Beyond.

a) Add the following closure statement to the RTF CAIB Recommendations listed below:

“Note: The Stafford-Covey Return to Flight Task Group held a plenary session on June 8, 2005, and NASA’s progress toward

answering this recommendation was reviewed. The Task Group agreed the actions taken were sufficient to fully close this

recommendation.”

p. 1-79, R 6.2-1 – Scheduling

p. 1-85, R 6.3-1 – Mission Management Team Improvements

p. 1-89, R 9.1-1 (7.5-1, 7.5-2, 7.5-3) – Detailed Plan for Organizational Change

p. 1-45, R 3.4-1 – Ground-Based Imagery

p. 1-53, R 3.4-3 – On-Vehicle Ascent Imagery

p. 2-5, SSP-3 – Contingency Shuttle Crew Support

NASA’s Implementation Plan for Space Shuttle Return to Flight and Beyond

July 7, 2005

b) Add the following statements to the RTF CAIB Recommendations listed below:

“Note: NASA has closed this recommendation through the formal Program Requirements Control Board process. The

following summary details NASA’s response to the recommendation and any additional work NASA intends to perform

beyond the

Columbia

Accident Investigation Board recommendation.”

p. 1-1, R 3.2-1 – External Tank Thermal Protection System Modifications

p. 1-15, R 3.3-2 – Orbiter Hardening and Thermal Protection System Impact Tolerance

p. 1-25, R 6.4-1 – Thermal Protection System On-Orbit Inspect and Repair

c) Add the following closure statement to the non-RTF CAIB Recommendations listed below:

“Note: NASA has closed this recommendation through the formal Program Requirements Control Board process. The

following summary details NASA’s response to the recommendation and any additional work NASA intends to perform

beyond the

Columbia

Accident Investigation Board recommendation.”

p. 1-41 R 3.8-2 – Reinforced Carbon-Carbon Spares

p. 1-73 R 4.2-4 – Micro-Meteoroid and Orbital Debris Risk

d) Add the following closure statement to the non-RTF CAIB Observations listed below:

“Note: NASA has closed this observation through the formal Program Requirements Control Board process. The following

summary details NASA’s response to the observation and any additional work NASA intends to perform beyond the

Columbia

Accident Investigation Board observation.”

p. 2-35, O 10.1-1 – Public Risk Policy

p. 2-57, O 10.5-2 – Orbiter Processing Improvements

p. 2-79, O 10.8-2 – Galvanic Coupling

p. 2-93, O 10.11-1 – Shuttle Maintenance Through 2020

e) Add the following closure statement to the Space Shuttle Program Actions listed below:

”Note: NASA has closed this Space Shuttle Program (SSP) action through the formal Program Requirements Control Board

process. The following summary details NASA’s response to the SSP Action and any additional work NASA intends to

perform beyond the SSP Action.”

p. 2-13, SSP-6 – Waivers, Deviations, and Exceptions

p. 2-21, SSP-10 – Contingency Action Plans

p. 2-29, SSP-14 – Critical Debris Size

NASA’s Implementation Plan for Space Shuttle Return to Flight and Beyond

July 7, 2005